Both dramas involve male lead that time travel to the past and using their modern skills solve problems with bits of romance too. MTH includes the ML getting 2 wives with a happy ending.

Both dramas involve male lead that time travel to a historical like period and using their modern skills solve crime.

Both dramas involve the male lead being transported to a historical period where they solve crimes.

Same "loser" MC with a girl with special powers that just shows up out of nowhere and rocks his world i suppose. The themes in both shows are quite similar even though Youkai GF is more action heavy. Similar shows, try the other if you seen the latter

Similar dynamic in both shows were the ML is human and the FL is a supernatural creature. Initially, both ML encounter the FL by breaking a curse / awakening them from another realm. If you like one, try the other.

Both similar in the way that its kinda like a rental / fake / not a standard relationship with a girl. in general both series give off a similar vibe. if you like one, you might like the other. although the mc in mousou kanojo i found to be trash. uve been warned

Similar shows. Both have FL that are "robots" and the male leads that grow fond of them. both robots fall in love with the human in some manner resulting in a similar ending for the robot.

Similar premise, female lead that is visually impaired and male lead that is kinda a gangsta. your eyes tell is a bit more emotional comparitively whilst koi desu is quite a fluffy romance drama :)

Both shows include the relationship between a "normal" girl and a "yakuza" male lead. Gokushufudo is more comedic whilst koi to dangan is more romance based. If you like the premise of the yakuza, both shows are pretty good.

Both are high quality dramas with a decent mix between seriousness and comedy. Joy of life, i would say has better plot and is focused more on strategy / mind games whilst Journey to love has a better "slow" yet charming romance. Romance in Joy of life barely exist. Still both shows have the capacity to keep you hooked from start to end. The most important, both shows develop characters really well ( the ML and FL develpment in Journey to Love is very well done, even the " princess' " shows growth). What i like the most is that the "typical" annoying character you see in every historical show (typically a princess or some stupid MC) arent present in these shows. Both leads in journey to love are smart, and Fan Xian in JOL is charming indeed. Try one, if you saw the other :)

Both dramas have ML with superpower (in Memorist - ML can look into the memories of whoever he touches, in The Game: Towards Zero - ML can see the moments before someones death when he looks into their eyes)
Both dramas FL is a detective / part of the police.
Both drama have FL suspect ML as being accomplice to crimes.
If you liked one, you will surely like the other!!

Both have the same concept of being able to see when someone dies and unable to prevent it. In about time, a clock on the persons body is used by the protagonist to tell when they will die.